Wednesday, July 19, 2017

When superstitious are good...

I just read the following paper:
Nunn, Nathan, and Raul Sanchez de la Sierra. Why Being Wrong can be Right: Magical Warfare Technologies and the Persistence of False Beliefs. No. w23207. National Bureau of Economic Research, 2017.
and I find it very interesting. Basically it is about why superstitions are good in certain cases. In this paper the author analyzes a case of a village in a Democratic Republic Congo. Namely, due to the unstable political situation there are lot of violence done  by different military groups that regularly attack villages. To protect themselves people in some villages believe they can be made resistant to bullets by strictly following a special magical procedure. It's obviously false but in case someone dies they prescribe the fault to not following this special magical procedure. This sounds crazy, but the effect is interesting. While it hurts individuals, it helps the collective since more people are willing to engage in defending villages with the end result of having 2 years of peace in this specific village that was brought as an example.

The key is that the utility of individual increases by everyone contributing to defense, but decreases when individual invests more. This, in effect, means that everyone will not invest the best he can and thus the collective will suffer! The superstition encourages everyone to give the best they can thus helping the collective. This is brilliant!

This result provokes some thinking as to whether some superstitions that I find annoying are actually beneficial, like religion for example. 

Sunday, July 16, 2017

Fedora 26 (kernel 4.11.9) and VMWare Workstation 12.5.7

I just upgraded Fedora 25 to Fedora 26 and of course there was a problem with VMWare Workstation. If you try to start vmware binary, it just silently fails. Anyway, I managed to find a solution here. In essence it is necessary to replace two share libraries and then manually compile vmmon and vmnet modules. The reason for this is that on Fedora GCC 7.1 is used which is a newer compiler that used to compile VMWare. So, to replace libraries, type:
# cp -r /usr/lib/vmware-installer/2.1.0/lib/lib/libexpat.so.0 /usr/lib/vmware/lib
# cd /usr/lib/vmware/lib/libz.so.1
# mv -i libz.so.1 libz.so.1.old
# ln -s /usr/lib64/libz.so.1 .
And to compile vmmon and vmnet you have to go into /usr/lib/vmware/modules/sources directory and unpack vmnet.tar and vmmon.tar files. Then, in each of them, issue make command. Finally, files ending with .ko move to /lib/modules/`uname -r`/misc (create it if necessary) and then run 'depmod -a' command. I also had to manually load those modules with 'modprobe vmnet' and 'modprobe vmmon' commands.

The only problem I noticed so far is that after inserting vmnet kernel module network interfaces are not automatically created. To fix that just run vmware-netcfg command and save configuration. After that, everything should be OK.

About Me

scientist, consultant, security specialist, networking guy, system administrator, philosopher ;)